Anything (within reason) is possible, and there are even a number of successful commercially available games developed using Game Maker and similar packages, so there's no reason a skilled developer couldn't do the same using Python assuming they choose a project of reasonable scope and put in the requisite effort.

There are two significant difficulties you might be likely to face using Python to create your games, although both can be worked around:

Python can sometimes be slower than some other languages, largely due to it's interpreted nature. Possible solutions to this include using alternative distributions such as PyPy, Cython or IronPython, or making use of modules written in lower level languages (often C or C++) for performance critical tasks.

Distribution isn't as straight-forward as with a compiled language where you end up with an executable file you can deliver. This is also a solvable problem however, using packages such as py2exe, PyInstaller, etc.

Python has actually been used in a number of big commercial games, usually as a scripting language on top of an engine implemented in a lower-level language -- a good example of this is the Panda3d engine, which is written in C++ but can be programmed using Python, and was used for a couple of Disney MMOs amongst other projects.

If you're happy to use Python, then yes, you should absolutely proceed with it, and yes, you can make a professional quality commercial game if you put in the time and effort to do so.

If you're looking for alternatives you might consider Unity, which can be programmed with C#, UnityScript (similar to JavaScript) or Boo (similar to Python), or even something like Construct 2 or Game Maker.

Define professional? A triple A game will hardly be written in python, as you will use some comercial expensive engine such as Unreal or CryEngine.

If you mean a comercial game, then yes, you can use python. Here are my 2c:

- If you intent on using Panda3D, you should know that it compiles for desktop and web browser, has been used for Toontown and pirates of the caribbean online. The biggest pain using Panda3D is the model format (egg). There is a project to add support to OBJ files.

- I don't know of any commercial game using pygame, but I haven't used it in a long, long time. I also know there is an android subset (link: http://pygame.renpy.org/ ). I do remember someone compiled it for IOS, but can't find the link, sorry

- There is also Kivy, a framework exclusively for mobile. They have made a few games to check if Apple Store would accept them, here is a link with more info: http://kivy.org/#contest

- AFAIK Unity3d accepts a python-like language named boo.

EDIT: must remember to press F5 before posting, went to check for links when the post had only one reply.

I don't know of many games that are truly Python based. Because the drawing libraries are usually C++ it often makes sense to use Python as a scripting layer on top of an engine framework. And, this has been done regularly.

What does that mean. It means that you can program the game in python, and use modules that calls on lower language (like C, or even C++) to run the game for you.

Panda3D is one example of this.

-Exo

If you take that logic to its conclusion, then you can't make a AAA game 'IN' C++, because somewhere down the line it inevitably uses a module that was written in C or even assembly.

Surely the main question is, "can I write a professional, commercial game where the only language I use during development is Python?" and the answer is most certainly yes. Writing the next Call of Duty is unlikely but there are many games that don't require that sort of performance and which can feasibly be sold.